1. Field of the Invention
The present invention relates to a detection device for detecting conditions at a target position by irradiating a laser light to the target position.
2. Description of the Related Art
In recent years, in order to improve driving safety, a detection device for detecting an obstacle ahead in a driving direction of a vehicle or the like by emitting a laser light to a target region is mounted, for example, on a family vehicle. The detection device scans a scan surface with a laser light to detect the presence or absence of the obstacle within the scan surface based on the presence or absence of a reflection beam of the laser light. The detection device emits pulse lights at each scan position (target position) to detect the presence or absence of the obstacle at the scan position. At the same time, the distance to the obstacle is measured based on the interval from pulse light emitting timing to pulse light receiving timing.
JP 10-38511 A describes a technique for adjusting the power of the laser light emitted from the detection device based on the power of the laser light received from the target region.
When this kind detection device is mounted, for example, on family vehicles, it may occur that, at the timing when the detection device mounted on a family vehicle emits the laser light to the target position, a detection device mounted on an oncoming family vehicle emits the laser light, which light is received by the photo detector in the detection device mounted on the vehicle. In this case, the detection device causes the false detection, and, depending on it, there is the case that non-desired driving control hangs over to the vehicle. These problems come to be frequent in future as the vehicles which mount this kind of detecting device increase.